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<div class="titlepage"><div><div><h3 class="title">
<a name="boost_asio.reference.IteratorConnectHandler"></a><a class="link" href="IteratorConnectHandler.html" title="Iterator connect handler requirements">Iterator
      connect handler requirements</a>
</h3></div></div></div>
<p>
        An iterator connect handler must meet the requirements for a <a class="link" href="Handler.html" title="Handlers">handler</a>.
        A value <code class="computeroutput">h</code> of an iterator connect handler class should work correctly
        in the expression <code class="computeroutput">h(ec, i)</code>, where <code class="computeroutput">ec</code> is an lvalue
        of type <code class="computeroutput">const error_code</code> and <code class="computeroutput">i</code> is an lvalue of
        the type <code class="computeroutput">Iterator</code> used in the corresponding <code class="computeroutput">connect()</code>
        or async_connect()` function.
      </p>
<h5>
<a name="boost_asio.reference.IteratorConnectHandler.h0"></a>
        <span class="phrase"><a name="boost_asio.reference.IteratorConnectHandler.examples"></a></span><a class="link" href="IteratorConnectHandler.html#boost_asio.reference.IteratorConnectHandler.examples">Examples</a>
      </h5>
<p>
        A free function as an iterator connect handler:
      </p>
<pre class="programlisting">void connect_handler(
    const boost::system::error_code&amp; ec,
    boost::asio::ip::tcp::resolver::iterator iterator)
{
  ...
}
</pre>
<p>
        An iterator connect handler function object:
      </p>
<pre class="programlisting">struct connect_handler
{
  ...
  template &lt;typename Iterator&gt;
  void operator()(
      const boost::system::error_code&amp; ec,
      Iterator iterator)
  {
    ...
  }
  ...
};
</pre>
<p>
        A lambda as an iterator connect handler:
      </p>
<pre class="programlisting">boost::asio::async_connect(...,
    [](const boost::system::error_code&amp; ec,
      boost::asio::ip::tcp::resolver::iterator iterator)
    {
      ...
    });
</pre>
<p>
        A non-static class member function adapted to an iterator connect handler
        using <code class="computeroutput">std::bind()</code>:
      </p>
<pre class="programlisting">void my_class::connect_handler(
    const boost::system::error_code&amp; ec,
    boost::asio::ip::tcp::resolver::iterator iterator)
{
  ...
}
...
boost::asio::async_connect(...,
    std::bind(&amp;my_class::connect_handler,
      this, std::placeholders::_1,
      std::placeholders::_2));
</pre>
<p>
        A non-static class member function adapted to an iterator connect handler
        using <code class="computeroutput">boost::bind()</code>:
      </p>
<pre class="programlisting">void my_class::connect_handler(
    const boost::system::error_code&amp; ec,
    boost::asio::ip::tcp::resolver::iterator iterator)
{
  ...
}
...
boost::asio::async_connect(...,
    boost::bind(&amp;my_class::connect_handler,
      this, boost::asio::placeholders::error,
      boost::asio::placeholders::iterator));
</pre>
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      M. Kohlhoff<p>
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